The above-referenced co-pending '317 application describes a portable telecommunications test system, diagrammatically illustrated in FIG. 1 as comprising a hand-held personal computer-based test and communications craft unit 10, through which a craftsperson, who has been directed by a dispatch center 11 to a service site located remotely with respect to a central office 12 serving a line 13 to be tested, may communicate with the central office and with a generic test head 14 that is connectable to the line under test. To reach the service site, the craftsperson employs a technician's service vehicle 20.
As described in the '317 application, the test system functionality of the supervisory control mechanism executed by the internal processor of the craft unit 10 provides the service technician with a user-friendly, icon-based, test procedure for facilitating the craftsperson performance of various tests on the line. In so doing, the portable craft unit 10 is able to interact with multiple types of existing operational support systems.
For this purpose, via a contact-sensitive (e.g., pen 15 touch-operated) video display panel 16 of hand-held craft unit 10, the craftsperson may selectively invoke one or more test operations represented by a set of analysis and test function-associated icons. In response to these selections, the internal control processor of craft unit 10 executes communication and signal processing operations associated with an identified test. The test head 14 proper performs data acquisition on demand from the computer within craft unit 10, including the execution of functional tests.
In order to communicate with a remote network facility (central office 12 or dispatch/data center 11), the craft unit 10 contains a transceiver interface, which is further interfaced with a communication and signal processing sub-system on board the technician's service vehicle 20. The communication and signal processing sub-system on board the van, in turn, links the craft unit 10 with the remote network facility, via either a short haul wireless link, or by way of an auxiliary back-up wireline link.
The central office facility 12 typically includes a central office switch 31, central office test devices 33, and a line-conditioning device 35, such as a direct access test unit (DATU), or (SASS) transmission conditioning system. The central office test devices 33 are capable of providing an interface with various operational support systems of the data center 11, such as a service vehicle dispatch, outside plant record database, automated testing systems, and electronic network schematics. The line-conditioning device (e.g. DATU or SASS) 35 within central office 12 provides the craftsperson with the ability to selectively conduct a number of tests of a line through the operation of either craft unit 10, or by invoking specified key combinations (sequences) from a standard craftsperson's telephone test set.
Within service van 20 is a battery-charging, communication and signal processing sub-system 21, that includes a network server 22, a long haul wireless interface 23, a printer 24, and a battery holder/charging station 25. The network server 22 contains a file server that provides additional processing power and electronic data storage, and performs auxiliary data processing tasks on demand from the craft unit 10. The long haul wireless interface 23 provides a wireless gateway to long haul wireless services. Printer 24 is available to print out various information, such as test results. Battery holder/charging station 24 receives and store the portable craft unit 10, so that unit 10 may be secured and stowed, and its associated power supply (battery pack) may be recharged, when not in use. (As will be described below, pursuant to a feature of the present invention, battery holder/charging station 24 is configured as a compact (hardware-efficient) storage and interconnect architecture, which includes a multi-pin signalling communication port that allows the craft unit 10 to operated in a hands-free `on-line` condition while being stowed and charged in battery holder/charging station 24.)
Because craft unit 10 is portable and is intended to used in a variety of environments, it is necessary that it be sealed from the introduction of contaminants (e.g., moisture and foreign matter, or dust) which are a source of potential degradation of the operation of the circuit components housed within the craft unit. Unfortunately, conventional connectors that are normally employed for telephone signalling (such as a four lead RJ11 connector) and digital data signalling (such as an eight lead DIN connector) have no provision for preventing the exposure of their leads to contaminants or preventing the introduction of foreign matter into the interior of the housing or case to which they are mounted.
In a conventional test set configuration, efforts to circumvent the contaminant-based degradation problem have included coating printed circuit assemblies with non-conductive passivating materials, coating the electrical contacts of individual components with non-conductive adhesives, and enclosing the printed circuit assemblies within a permanently sealed module. However, these previous proposals have proven to be less than satisfactory. It has been found that coating the printed circuit assemblies is inadequate, since during the coating process, the coating material tends to pull away from the sharp points at the ends of the electrical contacts of circuit components, which leaves them exposed to contamination. Coating the electrical contacts has been not been found to provide consistently robust protection, due to inconsistencies in the coating application process, so that contaminants are not completely sealed out. Finally, placing the printed circuit assemblies inside a permanently sealed enclosure prevents repairs or retrofits without destroying the seal, which cannot be restored.